CVE-2026-93009

Full vulnerability record from the local CVENow database.
Description

A flaw was found in dnsmasq. The DHCPv6 client hostname parser can read one byte past the end of a crafted FQDN option because it checks the next label length before confirming the pointer is still inside the option. An attacker on the local network can trigger this with a single DHCPv6 packet. The extra byte is not returned to the client or logged, and no crash has been demonstrated.
Severity
MEDIUM
CVSS score
4.3 (v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
[email protected]
Published
2026-10-29 14:18:00.367000
Last modified
2026-10-30 08:17:00.737000
View original CVE JSON
{
  "id": "CVE-2026-93009",
  "sourceIdentifier": "[email protected]",
  "published": "2026-10-29T14:18:00.367",
  "lastModified": "2026-10-30T08:17:00.737",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in dnsmasq. The DHCPv6 client hostname parser can read one byte past the end of a crafted FQDN option because it checks the next label length before confirming the pointer is still inside the option. An attacker on the local network can trigger this with a single DHCPv6 packet. The extra byte is not returned to the client or logged, and no crash has been demonstrated."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Red Hat",
          "product": "Red Hat Ceph Storage 9",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "rhceph/alloy-rhel10",
          "cpes": [
            "cpe:/a:redhat:ceph_storage:9"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 10",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "dnsmasq",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 6",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "dnsmasq",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:6"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 7",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "dnsmasq",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:7"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "dnsmasq",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:8"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 9",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "dnsmasq",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:9"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat OpenShift Container Platform 4",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "openshift4/ose-baremetal-runtimecfg-rhel8",
          "cpes": [
            "cpe:/a:redhat:openshift:4"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat OpenShift Container Platform 4",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "openshift4/ose-baremetal-runtimecfg-rhel9",
          "cpes": [
            "cpe:/a:redhat:openshift:4"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat OpenShift Container Platform 4",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "openshift/ose-rhel-coreos-8",
          "cpes": [
            "cpe:/a:redhat:openshift:4"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat OpenShift Container Platform 4",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "openshift/ose-rhel-coreos-9",
          "cpes": [
            "cpe:/a:redhat:openshift:4"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat OpenShift Container Platform 5",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "openshift5/ose-baremetal-runtimecfg-rhel9",
          "cpes": [
            "cpe:/a:redhat:openshift:5"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat OpenShift Container Platform 5",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "openshift/ose-rhel-coreos-9",
          "cpes": [
            "cpe:/a:redhat:openshift:5"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat OpenStack Platform 13 (Queens)",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "dnsmasq",
          "cpes": [
            "cpe:/a:redhat:openstack:13"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat OpenStack Platform 18.0",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "rhoso-operators/infra-rhel9-operator",
          "cpes": [
            "cpe:/a:redhat:openstack:18.0"
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
          "baseScore": 4.3,
          "baseSeverity": "MEDIUM",
          "attackVector": "ADJACENT_NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 1.4
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://access.redhat.com/security/cve/CVE-2026-93009",
      "source": "[email protected]"
    },
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2536083",
      "source": "[email protected]"
    }
  ]
}